1. Field of the Invention
The present invention relates to a robot control apparatus, in particular, relating to a control apparatus provided with a function for giving notification of maintenance and inspection times of peripheral devices that operate in cooperation with an automaton such as a robot, machine tool or the like.
2. Description of the Related Art
Recently, in order to reduce unexpected downtime, functions which urge the user to perform periodical maintenance of a robot have been developed and applied. A robot operates as a system, and in most automated systems, automatons such as robots, machine tools and the like control their peripheral devices by DO (digital output) signals, etc., so as to perform operations in cooperation therewith. Accordingly, for the automated system to operate normally, it is necessary to maintain and inspect correctly not only the robot or machine tool but also their peripheral devices. However, the intervals of maintenance and inspection are not the same so it is difficult for the user to know the timings of maintenance and inspection for different devices.
There have been known inspection timing notifying apparatuses for industrial robots which calculate cumulative times of actual operation for components of the industrial robot and gives notification of the times of inspection when the cumulative operating time of each component reaches a predetermined time (e.g., Japanese Unexamined Patent Publication (Kokai) No. S58-223594, which will be referred to hereinbelow as “Patent Document 1”). In what is assumed to be the usual method, whereby maintenance and inspection is performed at constant intervals, it is not possible to check individual components at the optimum timing for each of them. In other words, there is a risk or possibility that some components have already reached the end of their service life while others unnecessarily undergo maintenance and inspection. In the apparatus described in Patent Document 1, the optimal maintenance and inspection timings for individual components can be determined.
There has been a known numerically controlled apparatus that, at each time of inspection, determines the next timing of inspection based on the variation of state quantity from the previous inspection, and notifies the timings of inspection for components of a machine tool (e.g., Japanese Unexamined Patent Publication (Kokai) No. 2014-174680). In this apparatus, the interval of inspection is set to be long while the variation of state quantity is small, whereas the interval of inspection is set to be short while the variation of state quantity is large, whereby it is possible to perform inspection at the optimal timing for each component.
Applying such functions or combinations thereof to a robot, machine tool or the like which constitute the automated system makes it possible to properly perform maintenance and inspection thereon. However, the components that constitute an automated system are not always controlled by a controller including a processor and storage as in the robot or machine tool, but there are many peripheral devices that operate in accordance with the signals from the control apparatus of the robot or machine tool. In order for each of these peripheral devices to add up the actual time of operation and measure and record the state quantity, it is necessary to provide an additional device, hence such functions are not easy to implement.